Hyperemesis Gravidarum (HG)

Vomiting in first trimester common; only HG if excessive, protracted, altering quality of life

Pathophysiology

  • The placenta produces hCG during pregnancy
  • This hormone is thought to be responsible for nausea and vomiting
  • Nausea and vomiting are more severe in molar pregnancies and multiple pregnancies due to the higher hCG levels
  • It also tends to be worse in the first pregnancy and overweight or obese women

Clinical presentation

  • Dehydration, ketosis, electrolyte and nutritional disbalance
  • Weight loss, altered liver function
  • Signs of malnutrition
  • Emotional instability, anxiety, severe cases can cause mental health issues e.g. depression

Investigations

  • The RCOG guideline (2016) criteria for diagnosing hyperemesis gravidarum are ‘protracted’ NVP plus:
    • More than 5% weight loss compared with before pregnancy
    • Dehydration
    • Electrolyte imbalance
  • Severe HG may be associated with fetal growth restriction, hence growth scans are advised

Management

  • Rehydration IV, electrolyte replacement
  • Parenteral antiemetic
    • First line: cyclizine, prochlorperazine
    • Second line: metoclopramide
  • Nutritional supplement
  • Vitamin supplement: thiamine/pabrinex
  • NG feeding, Total Parenteral Nutrition (TPN)
  • Steroid use in recurrent, severe cases
  • Thromboprophyaxis
  • Can rarely extend to second trimester or even throughout pregnancy - in severe cases termination of pregnancy may be needed if health of woman is severely compromised